The present invention relates generally to transfer systems, and more specifically to an offloading system for removing strip-like products such as sliced bacon arranged side-by-side from a first unidirectionally driven conveyor, and for rearranging the products in predetermined serial groupings on a second conveyor. The system finds particular utility for offloading fried bacon strips from the endless conveyor of a bacon frying oven, and for shingling the off-loaded bacon strips in predetermined groups for packaging.
Bacon frying ovens of the type to which the present invention is particularly adapted employ a wide continuously moving conveyor belt on which bacon strips are arranged side-by-side in transverse rows. As the bacon strips progress through the oven a second continuously moving belt is brought down on top of the bacon slices. The two belts, with the bacon strips pressed flat inbetween, are driven between heated platens which simultaneously apply pressure and heat to fry the bacon strips. After the bacon strips have been fried the second belt is removed to enable the bacon strips to be removed from the conveyor belt.
For efficient operation of such bacon frying ovens it is necessary that the bacon strips be arranged to provide maximum utilization of the conveyor belt surface. That is, the bacon strips must not be so close together as to stick together during the frying operation, or so far apart as to cause large areas of the belts to be heated and pressed with no bacon strips therebetween. Accordingly, it has become standard practice to arrange the bacon strips lengthwise side-by-side in transverse rows extending across the entire width of the belt, the transverse rows being equally spaced along the entire length of the top surface of the conveyor belt. Furthermore, since the oven platens must necessarily be continuously heated and short term temperature changes are not practicable it is highly desirable for consistent frying action that the fryer oven conveyor move continuously at a predetermined constant speed.
The need for loading and offloading bacon strips from the oven conveyor without interfering with the operational efficiency of the oven has presented a need for loading and unloading systems capable of automatically handling the thin strips of bacon with a high degree of precision and in a manner which interfaces with the cyclic operation of up-line and down-line processing machinery. The co-pending application of the present inventors, Ser. No. 447,392, filed Mar. 1, 1974 and assigned to the present assignee, is directed to a system meeting these criteria which is eminently well suited for loading the oven conveyor with limp unfried bacon slices, and the present application is directed to a system meeting these criteria for offloading prefried bacon slices from the oven conveyor.
Accordingly, it is an object of the present invention to provide a system for grouping a finite number of items serially arranged on a unidirectionally-driven conveyor into individual groups each having a predetermined number of items.
It is another object of the present invention to provide a system for grouping items serially arranged along a continuously moving conveyor into groups having a predetermined number of items each, and for shingling the items in each group and depositing the shingled groups onto underlying parchment paper for subsequent packaging.